In programming object model has two related but different meanings:

     1. Properties of objects in general, on a particular programming language, computer technology, notation or methodology that uses them. For example, the Java object model, a model of a COM object or the object model of OMT. Such models are usually the object is determined by such concepts as class, message, inheritance, polymorphism and encapsulation. There is extensive literature on formal models of the object as a subset of the formal semantics of programming languages.
     2. The collection of objects or classes in which the program can examine and manipulate some parts of his world. In other words, object-oriented interface of some services or systems. This interface is called the object model provided services or systems. For example, Document Object Model (DOM) is a set of objects that represent a page in a browser, used by script programs to examine and dynamically change the page. There is a Microsoft Excel object model to control Microsoft Excel from another program, and the driver ASCOM telescope object model for the control of astronomical telescopes.